Apparatus and a method for separating particles from hot gases

Abstract

An apparatus that includes (i) a centrifugal separator assembly and (ii) a fluidized bed reactor having a reactor chamber, the separator assembly being connected to the reactor and provided for separating solid particles from gas discharged from the reactor chamber. The apparatus includes planar peripheral walls defining a vortex chamber, having a rectangular cross section, the vortex chamber having an interior gas volume in which at least two vertical gas vortices can be formed, and the planar peripheral walls including a first wall portion connecting the separator assembly to the reactor chamber, at least two gas outlets, disposed one after the other in the longitudinal direction of the vortex chamber, for discharging cleaned gas from the gas volume, at least one solid particles outlet for discharging separated solid particles from the gas volume, and at least one gas inlet, arranged in the first wall portion, for introducing gas from the reactor chamber into the gas volume. The at least one gas inlet includes at least two inlet ducts which are mainly perpendicular to the first wall portion and arranged side-by-side in the first wall portion within a less than ninety degree sector of one gas vortex within the vortex chamber.

What is claimed is:  
     
       1. An apparatus comprising (i) a centrifugal separator assembly and (ii) a fluidized bed reactor having a reactor chamber, the separator assembly being connected to the reactor and provided for separating solid particles from gas discharged from the reactor chamber, said apparatus comprising: 
       planar peripheral walls defining a vortex chamber, having a rectangular cross section, said vortex chamber having an interior gas volume in which at least two vertical gas vortices can be formed, and said planar peripheral walls including a first wall portion connecting the separator assembly to the reactor chamber;  
       at least two gas outlets, disposed one after the other in the longitudinal direction of the vortex chamber, for discharging cleaned gas from the gas volume;  
       at least one solid particles outlet for discharging separated solid particles from the gas volume; and  
       at least one gas inlet, arranged in the first wall portion, for introducing gas from the reactor chamber into the gas volume, said at least one gas inlet including at least two inlet ducts which are mainly perpendicular to the first wall portion and arranged side by side in the first wall portion within a less than ninety degree sector of one gas vortex within the vortex chamber.  
     
     
       2. An apparatus according to claim  1 , wherein the inlet ducts have a length to width ratio l/w>0.8, the length l being the length of the inlet duct in the gas flow direction and the width w being the mean horizontal cross-sectional width of the inlet duct. 
     
     
       3. An apparatus according to claim  1 , wherein the inlet ducts are vertical slots having parallel vertical inlet duct delimiting walls, the vertical height h of a slot being at least twice the mean horizontal cross-sectional width of the slot. 
     
     
       4. An apparatus according to claim  3 , wherein the vertical height h of a slot is ten times the mean horizontal cross-sectional width of the slot. 
     
     
       5. An apparatus according to claim  1 , wherein the at least two inlet ducts are formed in an opening in the first wall portion by dividing the opening with at least one vertical partition wall. 
     
     
       6. An apparatus according to claim  5 , wherein the peripheral walls of the vortex chamber are tube walls, made of a plurality of vertical tubes connected to form a tube system, and the at least one partition wall dividing the opening is made of greater than three vertical tubes connected to said tube system. 
     
     
       7. An apparatus according to claim  6 , wherein the at least one partition wall dividing the opening is made of greater than five vertical tubes connected to said tube system. 
     
     
       8. An apparatus according to claim  6 , wherein the at least one partition wall is disposed within the opening mainly perpendicular to the main plane of the first wall portion. 
     
     
       9. An apparatus according to claim  6 , wherein a vertical inlet duct delimiting side wall in the at least one of the inlet ducts is formed of vertical tubes bent out of the plane of the first wall portion, the tubes being bent into or out of the vortex chamber to form an inlet duct delimiting side wall perpendicular to the main plane of the first wall portion. 
     
     
       10. An apparatus according to claim  9 , wherein the vertical inlet duct delimiting side wall is made of greater than three tubes, which are connected to the tube system of the peripheral walls. 
     
     
       11. An apparatus according to claim  10 , wherein the vertical inlet duct delimiting side wall is made of greater than five tubes, which are connected to the tube system of the peripheral walls. 
     
     
       12. An apparatus according to claim  1 , wherein the vortex chamber comprises: 
       a common wall portion between the vortex chamber and the reactor chamber, said common wall portion including the first wall portion;  
       a first side wall and a second side wall, perpendicular to the common wall portion; and  
       a third side wall opposite to and at least in its upper part parallel to the common wall portion,  
       wherein the peripheral walls are formed of vertical tubes mechanically connected side by side and forming a peripheral wall tube system.  
     
     
       13. An apparatus according to claim  12 , wherein the peripheral walls are mechanically connected side by side by fins. 
     
     
       14. An apparatus according to claim  12 , wherein the inlet ducts are formed in an opening in the common wall portion between two adjacent vortices, for introducing gas into both of the two adjacent vortices. 
     
     
       15. An apparatus according to claim  14 , wherein the vertical delimiting walls of the inlet ducts are formed of at least one partition wall, disposed perpendicular to the main plane of the common wall portion and formed of vertical tubes connected to the peripheral wall tube system, and vertical tubes bent out of the plane of the common wall portion, the tubes being bent into or out of the vortex chamber to form an inlet duct delimiting side wall, inclined greater than sixty degrees to the main plane of the common wall portion. 
     
     
       16. An apparatus according to claim  15 , wherein the inlet duct delimiting side wall is perpendicular to the main plane of the common wall portion. 
     
     
       17. An apparatus according to claim  14 , further comprising two gas outlets disposed within the vortex chamber, for forming two gas vortices therein, one vertical opening formed in the middle of the common wall portion, and two inlet ducts formed in the opening by (i) disposing a vertical partition wall in the middle of the opening, for forming a first inlet duct delimiting wall in each of the two inlet ducts, and (ii) bending vertical tubes at the opening area out of the plane of the common wall portion, for forming a second inlet duct delimiting wall in each of the two inlet ducts. 
     
     
       18. An apparatus according to claim  14 , wherein greater than three vertical tubes are bent out of the plane of the common wall portion. 
     
     
       19. An apparatus according to claim  18 , wherein the vertical tubes bent out of the plane of the common wall portion are used for forming the vertical delimiting side walls of the inlet ducts. 
     
     
       20. An apparatus according to claim  14 , wherein greater than five vertical tubes are bent out of the plane of the common wall portion. 
     
     
       21. An apparatus according to claim  20 , wherein the vertical tubes bent out of the plane of the common wall portion are used for forming the vertical delimiting side walls of the inlet ducts. 
     
     
       22. An apparatus according to claim  14 , wherein the partition wall is mechanically connected to the common wall portion above and/or below the inlet ducts and additionally by its prolongation to the lower part of the third side wall of the vortex chamber. 
     
     
       23. An apparatus according to claim  14 , wherein the partition wall is mechanically connected to the common wall portion above and/or below the inlet ducts and additionally by its prolongation to supporting structures of one of the reactor chamber and the vortex chamber. 
     
     
       24. An apparatus according to claim  1 , wherein the first wall portion is made of a mainly homogeneous castable material and the inlet ducts are formed by casting in the castable material. 
     
     
       25. An apparatus according to claim  24 , wherein the inlet ducts have a length to width ratio l/w>0.8, the length l being the length of the inlet duct in the gas flow direction and the width w being the mean horizontal cross-sectional width of the inlet duct. 
     
     
       26. An apparatus according to claim  24 , wherein the axes of the inlet ducts are parallel. 
     
     
       27. An apparatus according to claim  24 , wherein the axes of at least two inlet ducts form an angle between 5° to 60°. 
     
     
       28. A method for separating solid particles from gas discharged from a reactor chamber, utilizing a centrifugal separator that includes a vortex chamber having a rectangular cross section and being delimited by peripheral walls including a planar first wall portion and having at least two gas outlets, at least one solid particles outlet and a gas inlet means arranged in the first wall portion, the method comprising: 
       discharging a gas and solid particle stream from the reactor chamber and introducing the stream through the gas inlet means into the vortex chamber;  
       separating solid particles from the gas in at least two gas vortices formed in the vortex chamber;  
       discharging separated solid particles from the vortex chamber through the at least one solid particles outlet;  
       discharging purified gas through the at least two gas outlets; and  
       dividing the gas and solid particle stream discharged from the reactor chamber in the gas inlet means into at least two adjacent streams and introducing the at least two streams mainly perpendicular to the first wall portion and within a less than ninety degree sector of a gas vortex into the vortex chamber.  
     
     
       29. A method according to claim  28 , further comprising guiding the at lest two gas and solid particle streams through inlet ducts having a length to width ratio l/w>0.8.